1. Field of the Disclosure
The present disclosure relates to the field of patient monitoring devices. More specifically, the disclosure relates to portable and handheld patient monitors, including pulse oximeter monitors, while other embodiments relate to various parameters displayed by these type of patient monitors.
2. Description of the Related Art
Caregivers often employ patient monitoring systems or devices, such as pulse oximeters, capnographs, blood pressure cuffs, and the like, for convenient spot checking and even continuous monitoring of physiological characteristics of a patient. Patent monitoring systems generally include one or more sensors applied to a patient, a monitoring device, and one or more cables connecting the one or more sensors and the monitoring device.
Portability of these monitoring systems is advantageous for a number of reasons. For example, portable devices provide the patient with mobility and provide the caregiver the option of including the monitoring device when transporting patients from one setting to another. For example, caregivers often transport patients from an ambulance to a hospital emergency room, and between surgical, intensive care, and recovery settings.
Some portable devices can also alleviate issues relating to incompatibility problems exacerbated by the prevalence of expensive and non-portable multiparameter patient monitoring systems. For example, some portable patient monitoring devices are capable of outputting information expected by one or more non-portable legacy multiparameter patient monitoring systems, where that output is used as an input for the non-portable systems.
One example of a patient monitoring device is a pulse oximeter, which is a widely accepted noninvasive procedure for measuring the oxygen saturation level of arterial blood, an indicator of oxygen supply. Early detection of low blood oxygen level is critical in the medical field, for example in critical care and surgical applications, because an insufficient supply of oxygen can result in brain damage and death in a matter of minutes. However, many other industries have adopted the detection of a person's oxygen supply into their monitoring and analysis regimens, including the fitness industry, home or corporate care industries, elderly care facilities and the like.
A pulse oximeter typically provides a numerical readout of the patient's oxygen saturation, a numerical readout of pulse rate, and an audible indicator or “beep” that occurs in response to each pulse. In addition, the pulse oximeter may display the patient's photo plethysmograph, which provides a visual display of the patient's pulse contour and pulse rate.
A portable pulse oximeter may be a standalone device, or as described in the foregoing, may be incorporated as a module or built-in portion of a multiparameter patient monitoring system, which also provides measurements such as blood pressure, respiratory rate, EKG, or the like. Exemplary pulse oximeters, including standalone pulse oximeters and portable pulse oximeters usable within a multiparameter system, are commercially available from Masimo Corporation of Irvine California, the Assignee of the present application. Aspects of such exemplary pulse oximeters are disclosed in U.S. Pat. Nos. 6,770,028, 6,584,336, 6,263,222, 6,157,850, 5,769,785, and their related patent and copending application families, each of which is incorporated herein by reference.
In many conventional patient monitoring devices, such as pulse oximeters, the interaction between a caregiver and the device is accomplished through user input keys and displayed data. The user input keys are arranged in a topology or layout similar to a table where the input keys are aligned in one or more rows and/or one or more columns. In portable devices, such layouts do not provide an intuitive feel, often requiring a user to use both hands to operate the device. For example, caregivers often use one hand to hold the device and the other to punch the input keys. Such layouts also often engage the full attention and concentration of the caregiver for operation. Moreover, such row and/or column key layouts can even lead to losing one's grip on the device when attempting single-handed operation or when inattentively operated. Loss of grip can lead to the device being dropped, knocked out of hand, off a counter, or the like, which can damage the device and/or lead to inaccurate patient monitoring.